There are many applications in academic, industrial, and medical fields that benefit from devices and methods that are capable of accurately and controllably delivering fluids, such as liquids and gases that have a beneficial effect when administered in known and controlled quantities. Such devices and methods can be particularly useful in the medical field where treatments for many patients include the administration of a known amount of a substance at predetermined intervals.
Insulin-injecting pumps have been developed for the administration of insulin for those suffering from both type I and type II diabetes. Some insulin injecting pumps configured as portable infusion devices can provide continuous subcutaneous insulin injection and/or infusion therapy for the treatment of diabetes. Such therapy may include the regular and/or continuous injection or infusion of insulin into the skin of a person suffering from diabetes, and offers an alternative to multiple daily injections of insulin by an insulin syringe or an insulin pen. Such pumps can be ambulatory/portable infusion pumps that are worn by the user and that may use replaceable cartridges. Examples of such pumps and various features that can be associated with such pumps include those disclosed in U.S. patent application Ser. No. 13/557,163, U.S. patent application Ser. No. 12/714,299, U.S. patent application Ser. No. 12/538,018, U.S. Provisional Patent Application No. 61/655,883, U.S. Provisional Patent Application No. 61/656,967 and U.S. Pat. No. 8,287,493, each of which is incorporated herein by reference.
Regulatory and other considerations require, e.g., that insulin pumps have a maximum bolus limit that may be defined as the maximum amount of insulin, that a user can have the pump deliver at any one time. Many pumps also enable a user to set a customized maximum bolus amount that is less than such a limit programmed into the devices. This limit provides a safety feature that prevents a user from inadvertently taking a bolus that is much larger than necessary and potentially unsafe. For example, a user intending to take a bolus of 4 units of insulin may inadvertently enter 44 units of insulin, which could potentially cause serious health concerns for the user. Additionally, the highest level at which the maximum bolus limit can be set is typically the same for all users, even though each user's needs typically are different from one another. For example, there may be a patient for whom a bolus amount that is unsafe for much of the population would be perfectly acceptable, yet that patient's pump may have a programmed maximum bolus limit that will prevent the patient from taking such a bolus. In addition, there are circumstances where it may be appropriate for a user to receive a bolus of medicament such as insulin that is larger than the user's customized maximum bolus limit. For example, a user's blood sugar level might be much higher than normal, or the user might have consumed a much larger number of carbohydrates than usual. In such a circumstance, the user's custom-set limit wilt prevent the user from taking such a complete bolus, even if it is warranted.
Therefore, there is a need for a system and a method that provides for greater flexibility in establishing, maintaining and/or changing maximum bolus limits in fluid pumps for delivery of medicament such as insulin.